Heavy duty pack



FIG. 1 is a perspective view of a heavy duty pack showing my new design.

FIG. 2 is a front elevation view of the heavy duty pack;

FIG. 3 is a rear elevation view of the heavy duty pack;

FIG. 4 is a left side elevational view of the heavy duty pack;

FIG. 5 is a right side elevational view of the heavy duty pack;

FIG. 6 is a top plan view of the adjustable cyclic device; and,

FIG. 7 is a bottom plan view of the heavy duty pack. 

CLAIM The ornamental design for a heavy duty pack, as shown and described. 